Oncogenesis is a process that involves the transformation of normal cells into Cancer cells.
Abnormalities of tumor suppressor/inducer genes:
Several proteins like p53 proteins are produced within the cells, whose function is to limit the cell division and to regulate certain parts of the cell cycle. The genes that code for these proteins are known as anti-oncogenes as they suppress the cell growth. The failure of anti-oncogenes leads to unregulated cellular division, which is the main characteristic of the Cancer cells.
Other groups of genes like proto-oncogenes are also present, which produce proteins and other substances that enhance cellular growth and proliferation. Excessive activity of these genes causes excessive cellular division and growth. Lack of regulation of these genes also results in abnormal growth of cell division and its growth.